The invention relates to a container arrangement comprising a plurality of flexible disposable bags, each of which has an inlet element, to which a flexible connecting tube is attached, wherein each connecting tube branches off from a flexible common main line, which has a common inlet section at the input end.
Furthermore, the invention relates to a method for filling the flexible disposable bags of such a container arrangement.
A container arrangement of this type is known from EP 1 525 138 B1. Such container arrangements follow the common trend in medical technology and biotechnology away from reusable containers to disposable containers that are designed to be used once and then disposed. The containers are constructed as flexible plastic bags with at least one inlet element. Each bag is attached to a main line via a flexible connecting tube that is assigned to each bag, and this main line is usually constructed as a flexible tube. The main line has an inlet section at the input end. The inlet section can be attached, for example, to a pump. It is well known that such container arrangements are marketed as prefabricated, sterile units. Their use takes place in a filling system, which has a plurality of pinch valves, wherein each connecting tube is inserted into an assigned pinch valve. The inlet section of the main line is attached to a pump that is connected to a supply container. It is also known to connect the inlet section of the main line directly to the supply container or to a cutoff valve that is assigned to that supply container. In this case the supply container is either pressurized per se or is positioned higher than the disposable bags that serve as the target bags in the container arrangement. The target bags can be filled one after the other from the supply container by opening the pinch valves individually in an alternating fashion. Preferably, at the same time the fill level of the target bags is monitored, for example, gravimetrically. The drawback with the known system is the lack of a degassing possibility for expelling the residual gas in the tubing system prior to filling the disposable bags. The result is that the residual gas is filled into at least one of the bags, a feature that is undesired in many cases.
EP 1 236 644 discloses a system for filling a target bag from a plurality of supply bags. All of the bags are connected to a common distributor through connecting tubes assigned to the respective bags. The distributor has a common central chamber, which has a plurality of inputs and outputs, each of which is closed by a switching valve. Each connecting tube is attached to such an input or output. A piston pump is connected to an additional input/output in the form of a typical injection syringe. A gas outlet nozzle, which is provided with a membrane filter, is connected to an additional input/output. In order to fill the bag, the piston of the piston pump is pulled back and pushed forward in phases; and at the same time the volume flow from the supply bags to the target bag is controlled by controlling the switching valves as required. The residual gas, which comes from the tubing system and which collects in the central chamber of the distributor, can be expelled by controlling, as required, the switching valve assigned to the gas outlet nozzle. A drawback with this arrangement is the technically intricate and, therefore, expensive configuration of the distributor that contains the switching valves. On the one hand, the distributor represents the central element of the tubing system, to which all of the connecting tubes have to be connected. On the other hand, the distributor cannot be constructed as a disposable element for cost reasons. Rather, the distributor is a reusable element that has to be cleaned and sterilized in a time-consuming and costly process after each usage. In other words, the typically sterile and prefabricated connecting tube-bag arrangements have to be coupled to a hygienically critical central element prior to each filling process, so that the coupling operation itself is also hygienically critical.